It is well known that the muzzle climb or lift when a gun is fired results from the reaction of the recoil against the support for the gun. The amount of lift is proportional to the recoil and the direction is determined by the manner in which the gun is supported, as for example by the body and arms of the person firing the gun. A right or left handed marksman holding a rifle in a typical right or left handed firing position respectively, will experience a rightward or leftward muzzle lift, respectively, at approximately 45.degree. to the vertical, whereas a gun typically supported on a bipod where the lateral forces are balanced will exhibit a vertical lift.
Muzzle brakes have been provided to reduce recoil and thereby to reduce muzzle lift, especially for larger guns, but such devices also dissipate much of the power that could otherwise be used to discharge the bullet and are distinguishable in operation from compensators which attempt to create a transverse force against the gun barrel in opposition to the direction of the muzzle climb, rather than to create an axial force on the barrel in opposition to the recoil.
An important object of the present invention is to provide an improved compensator for guns that is adjustably and detachably mountable on the muzzle braker, flash hider or flash suppressor of the gun barrel adjacent the muzzle having a number of circumferentially spaced ports (referred to herein as flash hider ports) that are effective in reducing the visibility or flash of the gases discharged from the barrel.
The flash hider ports are provided in a slightly enlarged diameter bore portion of the barrel at the muzzle end, which portion may be considered herein as an expansion chamber and part of the barrel, even though it is usually detachable from the gun to facilitate cleaning for example.
The flash hider ports extend generally radially through the barrel. Accordingly, when the gun is fired, gases flowing axially along the barrel enter the expansion chamber where a portion of their heat energy is converted to kinetic energy. Some of the gases are then discharged transversely of the barrel to the atmosphere. Although such ports are effective in reducing flash and in some instances are designed to reduce recoil and to compensate for muzzle climb, they do not by themselves serve effectively as a compensator because in order to be effective as a flash hider, much of the transversely discharged gas either has no effect in opposing muzzle lift, or actually increases the lift. Where the flash hider ports are designed to be more effective as a compensator, the flash hiding function is seriously impaired, as for example in accordance with the device shown in U.S. Pat. No. 3,971,285, to Ellis et al., where only two flash hider ports are available for use.
Other important objects of the present invention are thus to provide an improved compensator of the type described which is rotatably adjustable on a typical effective flash hider; which utilizes the gases that have already been expanded in the expansion chamber of the flash hider and have already been discharged transversely of the barrel via the flash hider ports; which comprises deflector means external to the flash hider for redirecting the transverse gas flow from one or more of the flash hider ports to oppose the muzzle lift effectively; which may be readily adapted for rotatable adjustment on most flash hiders now in use; and which has circumferentially spaced gas control portions selectively positionable with respect to the flash hider ports by the rotational adjustment for redirecting transversely discharged gases from the ports in predetermined transverse directions to compensate for left or right handed or vertical muzzle climb or lift, as determined by the adjustment.
By virtue of the present invention, some of the transversely discharged gases from the flash hider ports that would otherwise be ineffective in opposing muzzle lift, or might even enhance muzzle lift, are redirected to effect a reaction force opposing the muzzle lift. Furthermore, the energy of such gases that is now used in accordance with the present invention to oppose muzzle lift is extracted from the heat energy of the gases to reduce their temperature and accordingly their visible flash, resulting in minimum impairment of the flash hiding function. Also in contrast to the above mentioned Ellis et al compensator which can only use flash hider ports located above the horizontal axial plane of the gun barrel, the concept of the present invention as described below obtains effective compensation for muzzle lift from flash hider ports located at any circumferential position on the gun barrel. Most military rifles are equipped with flash hiders having circular cylindrical surfaces to accommodate grenade launching therefrom without concern for the angular position of the grenade on the flash hider. Accordingly the soldier in the field may readily adapt his gun to obtain effective compensation for muzzle lift merely by attaching the compensator described herein and rotatably adjusting the same to a desired position to accommodate his particular style of shooting, and in particular to compensate for either left or right hand use or bipod mounting, for example.
Another object is to provide such a compensator selectively adjustable rotatable on a flash hider to a number of selected positions and having locating means cooperable with the flash hider ports for securing the compensator at each selected position.
According to the invention the compensator may have a axially slotted portion fitting around the muzzle end of a gun barrel and the locating means for securing the element on the barrel may comprise a clip for tightening the slotted portion so that it clamps the gun barrel. Alternatively, the locating means may comprise a stop carried by the compensator for engaging a notch in the periphery of the barrel. The stop may be resiliently biased to engage the notch and may be retractable against the resilient biasing.
More specifically, the compensator may comprise a tubular element dimensioned to fit coaxially on the muzzle end of a gun barrel at the region of the flash hider and having at least one compensating vent means disposed or adapted to direct combustion gases discharged transversely from the flash hider ports primarily to one side of the barrel. The locating means for securing the element on the barrel may comprise a stop mounted on the element for passing therethrough and engaging in a flash hider port. The stop may be mounted on a lever for movement to and from a securing portion within the port.
Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.